Letting go of brackets is hard if you come from the C
school of bondage and discipline programming, where forgetting
something minor, like brackets on a function call, is
punishable by death ("Segmentation fault.").

When declaring arguments, I have found that the code
looks strange, inconsistent, and a little off-kilter when
mixing and matching declaration styles,
where 'off-kilter' is a euphemism for "looks broken":

Any statement like 'my $count = @_' can make me feel a little
bit dizzy, if only because it seems like anything could
happen there (i.e. concatenation with spaces, concatenation without,
first element assignment, last element assignment, count of items,
index of last item, etc.). Instead, I would rather explicitly
specify what is intended as 'my ($count) = scalar (@_);', though
rumor would have it that 'scalar' is deprecated.

Anyway, maybe I'm just behind the times. I use brackets on
int() and join(). I'll admit it! Maybe it's curable. As long
as I'm careful to make sure that my assignments are array-safe
(as I don't want to go to jail)
then things work okay, in their own wacky way, and everything is
bracketized and compartmentalized neatly.

So, I can only suppose that you would prefer the following
mutant variation, suggested for fun:

Just think of my as a really high precedence prefix operator that must
appear before an lvalue, and you'll have the right mental model. But to figure
the scalar-vs-arrayness of the rest of the expression, throw away all
the my's first.

My preference is one variable per my declaration, unless it's a bunch of scalars and an optional terminating array being fed from a list (like a subroutine argument grab).